The principal objective of the proposed research is the purification, physico-chemical and biochemical characterization of the LH-hCG receptor from the rich and readily available bovine corpora lutea in large quantities. In order to achieve the above goals, purification methods will be further modified to increase the yield and stability of the purified receptor. The purified receptor will be analyzed for the determination of S2OW and molecular weight using ultracentrifuge, sucrose-density gradient and SDS gel electrophoresis. The kinetics of binding (regulatory) and adenyl cyclase-catalytic subunit in terms of conditions required for optimum hormone interaction will be studied. The purified receptor will be subjected to lipid, carbohydrate and amino acid analyses. The relationship and properties of the soluble receptor will be examined. Effect of gangliosides on the coupling of the subunits of the receptors will be studied. Further characterization of the antibodies currently being produced against the receptor will be performed.